cfg: turn on internal asserts
board: enable GPIO ports on-demand for each periph

Enabling all GPIO ports in init_General is odd.

Conflicts:

	main.c
bld: homogenize the app rules

To have ifdef switches for board configuration, we will use
target-specific variables (not yet in this commit).

Conflicts:

	Makefile
board: gpio int callbacks for push buttons
main: support running without the UART
cfg: move Task module config closer to import

Conflicts:

	bld.cfg
log: timestamp time conv math to handle low freq
cfg: turn on INFO diags, userful for print logs
main: flash an LED on startup
app: button: handle push buttons

Conflicts:

	Makefile
app: pwm: generate a pwm signal

This is the app used for generating the external clock signal
for the system timer using a secondary helper board.
app: timer: test a timer handler
app: clock: test a clock function handler
main: safety button for debugger connect

Conflicts:

	Makefile
button: make the second button a safety wakeup
main: deduplicate the safety wakeup button code

Conflicts:

	Makefile
main: factored delay funcs into separate file
bld: added headers to dependency list
busy: a while(1) busy-loop app
main: comment about platform config

Conflicts:

	main.c